Noise control system, a noise control device and a method thereof

Abstract

A noise control system comprises a feedforward module, a feedback module, an error pre-processing module, and a signal integrating module. The feedforward module is configured to receive a reference signal and output a feedforward anti-noise signal by performing feedforward processing to the reference signal. The feedback module is configured to receive an error signal and output a feedback anti-noise signal by performing feedback processing to the error signal. The error pre-processing module is configured to receive the error signal and output a first pre-processing signal to the feedforward module and a second pre-processing signal to the feedback module. The signal integrating module is configured to output an integrated anti-noise signal integrated from the feedforward anti-noise signal and the feedback anti-noise signal. Wherein the first pre-processing signal corresponds to the first part of the error signal which belongs to the first frequency region; the second pre-processing signal corresponds to the second part of the error signal which belongs to the second frequency region.

What is claimed is: 
     
       1. A noise control system, comprising:
 a feedforward module configured to receive a reference signal and output a feedforward anti-noise signal by performing feedforward processing to the reference signal; 
 a feedback module configured to receive an error signal and output a feedback anti-noise signal by performing feedback processing to the error signal; 
 an error pre-processing module configured to receive the error signal and output a first pre-processing signal to the feedforward module and output a second pre-processing signal to the feedback module; and 
 a signal integrating module configured to integrate the feedforward anti-noise signal and the feedback anti-noise signal to output an integrated anti-noise signal; 
 wherein the first pre-processing signal corresponds to a first part of the error signal which belongs to a first frequency region; the second pre-processing signal corresponds to a second part of the error signal which belongs to a second frequency region; 
 wherein the first frequency region is at least partially lower than the second frequency region. 
 
     
     
       2. The noise control system of  claim 1 , wherein the error pre-processing module comprises:
 a component of noise bandwidth detection configured to receive the error signal; 
 a first pre-filtering component coupled to the component of noise bandwidth detection and configured to output the first pre-processing signal; and 
 a second pre-filtering component coupled to the component of noise bandwidth detection and configured to output the second pre-processing signal. 
 
     
     
       3. The noise control system of  claim 2 , wherein the first pre-filtering component is a low-pass filter, and the second pre-filtering component is a band-pass filter. 
     
     
       4. The noise control system of  claim 2 , wherein the first pre-filtering component and the second pre-filtering component are infinite impulse response filters. 
     
     
       5. The noise control system of  claim 2 , wherein the error signal has a periodic signal component, and the component of noise bandwidth detection adjusts the second frequency region based on the periodic signal component. 
     
     
       6. The noise control system of  claim 2 , wherein the component of noise bandwidth detection computes the frequency distribution of the error signal and adjusts the filtering region of the first pre-filtering component and the second pre-filtering component based on the frequency distribution. 
     
     
       7. The noise control system of  claim 1 , wherein the feedforward module adjusts at least a parameter of the feedforward processing according to the first pre-processing signal; the feedback module adjusts at least a parameter of the feedback processing according to the second pre-processing signal. 
     
     
       8. A noise controlling device, comprising:
 a noise control system, comprising:
 a feedforward module configured to receive a reference signal and output a feedforward anti-noise signal by performing feedforward processing to the reference signal; 
 a feedback module configured to receive an error signal and output a feedback anti-noise signal by performing feedback processing to the error signal; 
 an error pre-processing module configured to receive the error signal and output a first pre-processing signal to the feedforward module and a second pre-processing signal to the feedback module; and 
 a signal integrating module configured to integrate the feedforward anti-noise signal and the feedback anti-noise signal to output an integrated anti-noise signal; and 
 
 a first vibration sensor configured to sample a target sound and output the reference signal; 
 a sound producer configured to receive the integrated anti-noise signal and produce an offset sound; and 
 a second vibration sensor configured to sample a noise-reduced sound and output the error signal; 
 wherein the first pre-processing signal corresponds to a first part of the error signal which belongs to a first frequency region, and the second pre-processing signal corresponds to a second part of the error signal which belongs to a second frequency region; 
 wherein the noise-reduced sound is the sum of the target sound and the offset sound; 
 wherein the first frequency region is at least partially lower than the second frequency region. 
 
     
     
       9. A noise control method, comprising:
 receiving an error signal and outputting a first pre-processing signal and a second pre-processing signal; wherein the first pre-processing signal corresponds to a first part of the error signal which belongs to a first frequency region, and the second pre-processing signal corresponds to a second part of the error signal which belongs to a second frequency region; 
 receiving a reference signal and outputting a feedforward anti-noise signal after performing feedforward processing to the reference signal; 
 outputting a feedback anti-noise signal after performing feedback processing to the error signal; and 
 integrating the feedforward anti-noise signal and the feedback anti-noise signal and outputting an integrated anti-noise signal; 
 wherein the first frequency region is at least partially lower than the second frequency region. 
 
     
     
       10. The noise control method of  claim 9 , wherein the error signal has a periodic signal component, and a component of noise bandwidth detection adjusts the second frequency region based on the periodic signal component. 
     
     
       11. The noise control method of  claim 9 , when receiving the error signal and outputting the first pre-processing signal and the second pre-processing signal, computing the frequency distribution of the error signal, and adjusting the filtering region of the first pre-filtering component and the second pre-filtering component based on the frequency distribution. 
     
     
       12. The noise control method of  claim 9 , wherein the feedforward module adjusts at least a parameter for the feedforward processing according to the first pre-processing signal; the feedback module adjusts at least a parameter for the feedback processing according to the second pre-processing signal.